Problem: Solve for $q$ : $7 + q = -24$
Subtract $7$ from both sides: $ \begin{eqnarray} \\ 7 + q &=& -24 \\ \\ {-7} && {-7} \end{eqnarray} $ $ \begin{eqnarray} \hphantom{7 + q} &\hphantom{=}& \hphantom{-24} \\ q &=& -24 {- 7} \\ \end{eqnarray} $ Simplify. $ q = -31$